[scarrafan]

Hi all,

I own a GLA 250 2017 edition and have run into car battery problems.

Context: Have not been driving the car consistently due to COVID.
Wanting to use the car recently 2 weeks ago, I had to jump-start it since the batteries died out probably due to lack of use for more than a month.
The next time I touched the car was a week later, which I then had to jump-start the car again. Feeling weird that the battery ran out so quick I checked to see if my car would
run properly without a jump start 2 days later and lo and behold, the car battery ran out again.

Part of the reason might be because I'm not letting the car battery charge long enough after the jump start.
I drive 15-20 minutes after every jump start but don't know if it is enough.

Another thing I noticed was the latest time after I jump started my car, a warning sign appeared reading "auxiliary battery malfunction". Reading up on that, it doesn't seem to have anything to do with the problem of my car battery dying.

Just wanted to hear some opinions on what I should do next. Is it a problem with my car battery not charging properly and should I drive it longer for like 30-1 hour or should I see my dealer and just get my battery replaced. Thanks in advance.

 

[Wayne]

Short trips won't fix a drained battery. Parasitic drains will take it right back to its non starting status.

Best advice I've got is to get a good battery tender. There are cheap ones and better ones. I've got a Black & Decker as well as a CTek. They both work but I believe the CTek works better. Especially for desulphating the plates after the battery has discharged below 8 VDC.

 

[Huey52]

Battery Tender Junior is my favorite and have used them (interior & exterior models) for a long time. A month of disuse is the tipping point for needing same given all the parasitic drain from modern automotive computers. Short money for battery preservation and peace of mind.

And as Wayne also cites a short trip (e.g. your 15-20 minutes) is inadequate to recharge from such a low starting point.

You should be fine after a couple/few days of battery tending (the tender will indicate when recharged) however note that if you hadn't driven in a number of months you might have depleted/sulphated to a point of non-recovery. "Deep cycle" batteries are designed for such depletions but not so standard lead-acid.

 

[BriLyn421]

Hi all,

I own a GLA 250 2017 edition and have run into car battery problems.

Context: Have not been driving the car consistently due to COVID.
Wanting to use the car recently 2 weeks ago, I had to jump-start it since the batteries died out probably due to lack of use for more than a month.
The next time I touched the car was a week later, which I then had to jump-start the car again. Feeling weird that the battery ran out so quick I checked to see if my car would
run properly without a jump start 2 days later and lo and behold, the car battery ran out again.

Part of the reason might be because I'm not letting the car battery charge long enough after the jump start.
I drive 15-20 minutes after every jump start but don't know if it is enough.

Another thing I noticed was the latest time after I jump started my car, a warning sign appeared reading "auxiliary battery malfunction". Reading up on that, it doesn't seem to have anything to do with the problem of my car battery dying.

Just wanted to hear some opinions on what I should do next. Is it a problem with my car battery not charging properly and should I drive it longer for like 30-1 hour or should I see my dealer and just get my battery replaced. Thanks in advance.

* 2015 GLA 4MATIC Owner here && although I replaced my battery for peace of mind, I too recently received the auxiliary battery warning and its honestly fairly simple to replace yourself. (If you're into that kind of stuff lol) HOWEVER. For the auxiliary battery, that is located on the passenger side beneath the glove compartment. You'll have to pull back the panel and filter cover to expose the battery but it just slides out and in. Of course there's a few more specifics with how the exhaust valve connects with the cover BUT, just as a quick response/ FYI, I hope that helps.

 

[scarrafan]

Since then I took your advice and purchased a battery tender. The make and model is a 4.5 amp battery tender by Deltran which runs both 12 V and 6 V. Problem is after connecting the battery tender, everything works fine for 2 minutes (green lights on 12V and AGM/flooded which I assume is the correct battery type, and stable amber led for battery level which means that the battery is charging), but then the green light next to 12 V starts blinking after the 2-minute mark.

Looking at the user guide a blinking green light means either an incorrect battery voltage has been selected or the battery is defective. I'm just confused as to why the light would be stable for the first 2 minutes and then blink afterward. Looking online didn't really give me any answers so I was wondering if you guys can help again. Thanks in advance.

 

[Huey52]

Yes, AGM/flooded is lead-acid and of course 12V should also be selected.

I believe a flashing green light indicates 80% charged and you should leave on the charger until a steady green light which is 100% charged.

 

[scarrafan]

Sorry I meant the 12V light starts flashing. So it turns from green to blinking green and the battery level stays at amber.

 

[Huey52]

The only thing I can think of is that the cable connections aren't well seated/clamped and therefore the tender can't sense the battery voltage at the assigned 12VDC?

 

[Wayne]

With tenders that auto switch between 6 and 12 volts, if your battery is discharged below 7 volts the tender may not be able to properly assess the 12 volt battery, getting it mixed up with a 7 volt type. Do you have a volt meter to read the current status of the battery?

 

[scarrafan]

I do not have a voltmeter on hand but I can get my hands on one tomorrow. I tried to trickle charge the car right after a jump start, so I would not know how many volts the battery currently holds.

 

[Huey52]

Most of the better automotive and battery stores can do a chemical analysis on your battery to ascertain its present ability to hold a charge. Keep in mind that lead-acid batteries store chemical energy and provide electrical energy on demand so the typical chemical analysis has merit wrt storage capacity.

Voltage level is of course necessary and important but more so cold cranking amps to start your vehicle.

 

[Shadofax]

Once you've jump started the battery a couple times, I'd say no matter what you do with trickle charging, you've damaged the battery and it's time to buy a new one, and with not driving regularly, just keep in mind the need to put the tender on at times, don't let it sit a month. Not good not driving and warming up the mechanical components as well.

 

[Ptothe0]

My ‘16 GLA 250’s battery was 100% dead. It is currently sitting in the garage charging on a black and decker charger. The charger reads 6.7v - 7.1v. First question: at that point is the voltage too low to the point of no return?
Second: It concerns me that the headlights and tail lights come on and I can hear a ticking sound coming from somewhere between the charging ports and the headlights on the car. Any and all help is greatly appreciated!

 

[Wayne]

Any battery tender that is rated for both 6 and 12 volt batteries won't work on a 12 volt battery that is below about 7 volts. This includes B&D. The battery is analyzed as 6 volts and the tender limits the charge.

Buy a 12 volt only charger. Ideally the charger should have a desulphating mode. Look into CTek would be my advice.

 

[gbarringer]

I think Plothe0 might be using a B&D battery charger and not a battery tender. If it like my B&D charger you can select 6 or 12 volts

I would make sure everything is turned off and not using power. You might be hearing something trying to come on but the power level is too low so it is turning on and off. Possible disconnect the battery and hook the charge directly to the disconnected battery. If the charge has a jump-start feature maybe try jump-starting and take the car for a nice drive.to recharge the battery.

 

[Ptothe0]

Well guys, I ended up talking to the dealership. They allowed me to take the battery out and bring it in without towing the car and bringing it in to them. I got the replacement battery, the SA told me there would be no issues with swapping the battery out as the new one was the same specs, voltage, etc. I swapped it out and car turned on.

I let it run for about 10 minutes and then tried to shift it to reverse... NOTHING. Now I have a car that turns on but will not shift out of Park. Any ideas or suggestions?